Pharmacokinetics of ponazuril after oral administration to healthy llamas (Lama glama).

Objective—To determine the pharmacokinetics after oral administration of a single dose of ponazuril to healthy llamas. Animals—6 healthy adult llamas. Procedures—Ponazuril (20 mg/kg) was administered once orally to 6 llamas (day 0). Blood samples were obtained on days 0, 0.5, 1, 2, 3, 4, 5, 6, 7, 9, 11, 14, 21, 28, 35, 42, and 49. Serum ponazuril concentrations were determined by use of a validated reverse-phase high-performance liquid chromatography assay with UV absorbance detection. Pharmacokinetic parameters were derived by use of a standard noncompartmental pharmacokinetic analysis. Results—Mean ± SD area under the serum concentration–time curve was 7,516 ± 2,750 h•mg/L, maximum serum ponazuril concentration was 23.6 ± 6.0 mg/L, and the elimination half-life was 135.5 ± 16.7 hours. Serum concentration of ponazuril peaked at 84 hours (range, 48 to 120 hours) after administration and gradually decreased but remained detectable for up to 35 days after administration. No adverse effects were observed dur...